Add 28/12 and 21/40, Solve 2 4/12 + 21/40 as a fraction

Add 28/12 and 21/40

1^st number: 2 4/12, 2^nd number: 21/40

28/12 + 21/40 is 343/120.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 12 × 10 = 120,
28/12 = 28 × 10/12 × 10 = 280/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120
Add the two like fractions:
280/120 + 63/120 = 280 + 63/120 = 343/120
So, 28/12 + 21/40 = 343/120
In mixed form: 2103/120

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